Effect of conditioning regimen intensity on CMV infection in allogeneic hematopoietic cell transplantation.

Publication Type:

Journal Article


Biology of blood and marrow transplantation : journal of the American Society for Blood and Marrow Transplantation, Volume 15, Issue 6, p.694-703 (2009)


2009, Adolescent, Adult, Aged, Aged, 80 and over, Anti-Infective Agents, Bacterial Infections, Center-Authored Paper, Child, Child, Preschool, Clinical Research Division, Cohort Studies, Comparative Medicine Core Facility, Cytomegalovirus Infections, Disease Susceptibility, Female, Graft vs Host Disease, hematopoietic stem cell transplantation, Humans, Immunologic Memory, Immunosuppressive Agents, Incidence, Infant, Male, Middle Aged, Mycoses, Myeloablative Agonists, Postoperative Complications, Public Health Sciences Division, Research Trials Office Core Facility - Biostatistics Service, Retrospective Studies, RISK, Shared Resources, T-Lymphocyte Subsets, Transplantation Conditioning, Transplantation, Homologous, Vaccine and Infectious Disease Institute, Viremia, Whole-Body Irradiation, Young Adult


Nonmyeloablative conditioning is less toxic and results in initial establishment of mixed hematopoietic T cell chimerism for up to half a year with prolonged presence of host T cell immunity. In this study, we examined whether this translates into differences in the risks and/or severity of cytomegalovirus (CMV) infection and disease. We analyzed data from 537 nonmyeloablative (NM-HCT) and contemporaneous 2489 myeloablative hematopoietic cell transplant (M-HCT) recipients. In CMV seropositive recipients, no difference in the overall hazards of CMV infection at any level (adjusted hazard ratio [adj. HR] 0.9, 95% confidence interval [95% CI]: 0.7-1.0, P = .14) was noted; however, NM-HCT was associated with a lower risk of high-grade CMV infection (adj. HR 0.7, 95% CI: 0.5-0.9, P = .02). CMV disease rates were similar between the groups during the first 100 days after HCT, but NM-HCT recipients had an increased risk of late CMV disease (adj. HR 2.0, 95% CI 1.2-3.4). The increased risk of late CMV disease after NM-HCT was pronounced during the earlier years of the study period, but not detectable in more recent years. Contrary to earlier reports, survival following CMV disease was not reduced after NM-HCT when compared to M-HCT recipients. These results suggest that residual host cells after NM-HCT reduce progression to higher CMV viral load in NM-HCT recipients; however, this effect does not appear to protect against serious complications of CMV. Therefore, CMV prevention strategies in NM-HCT recipients should be similar to those used in M-HCT recipients.